1. Field of the Invention
The present invention relates to a push button type switch device, and more particularly, to a switch device that prevents a contact failure from occurring at contact points.
2. Description of the Related Art
For example, Patent document 1 discloses a conventional push button type switch.
In the switch disclosed in Patent document 1, when a key top is pushed down, a dowel part provided below the key top uniformly pushes a driven element down and the entire surface of a movable contact point is brought in contact with a stationary contact point, thereby functioning as a switch.
Also, since the key top is returned to its original state by a resilient force of an arm when pressing against the key top is released, the key top is adapted to release the contact state between the movable contact point and the stationary contact point.
[Patent Document 1]
Japanese Utility Model Application Publication No. 7-31471
However, the conventional switch disclosed in Patent document 1 is configured such that the movable contact point is simply pressed down to contact the stationary contact point. As a result, when dusts or stains are adhered to the movable contact point or the stationary contact point, or when the movable contact point or the stationary contact point is oxidized, a contact failure may be caused between the movable contact point and the stationary contact point.